function showhid(id){
	var d=document;
	if (!d.getElementById) return;

	var el;

	el=d.getElementById('tbl_'+id);
	if(el){
		if(el.style.display == 'block'){
			el.style.display='none';
			d.getElementById('div_'+id).innerHTML='+';
		}else{
			el.style.display='block';
			d.getElementById('div_'+id).innerHTML='-';
		}
	}
}
